In a UMTS (Universal. Mobile Telecommunications System) network, long-term evolution (LTE) is under study for the purposes of further increasing high-speed data rates, providing low delay, and so on (non-patent literature 1). In LTE, as multiple access schemes, a scheme that is based on OFDMA (Orthogonal Frequency Division Multiple Access) is used in downlink channels (downlink), and a scheme that is based on SC-FDMA (Single Carrier Frequency Division Multiple Access) is used in uplink channels (uplink).
Also, successor systems of LTE (referred to as, for example, “LTE-Advanced” or “LTE enhancement” (hereinafter referred to as “LTE-A”)) are under study for the purposes of further broadbandization and increased speed beyond LTE. In LTE (Rel. 8) and LTE-A (Rel. 9 and Rel. 10), MIMO (Multi-Input Multi-Output) techniques are under study as radio communication techniques to transmit and receive data using a plurality of antennas, and improve spectral efficiency. According to MIMO techniques, a plurality of transmitting/receiving antennas are provided in the transmitter/receiver, so that different transmission information sequences are transmitted from different transmitting antennas at the same time.